Recently, incision of the living tissue using laser light and the like has been commonly conducted since it is excellent in hemostasis. If the laser light is used, emission of the laser light from the front end of an optical fiber is concentionally conducted while the front end of the optical fiber is separated from a target tissue. However, by the reason of high damages to the apparatus components, irradiation of the living tissue with the laser light emitted from the surface of a probe has recently been conducted while the probe is in contact with the living tissue after the laser light has transmitted through the optical fiber to the emission probe and been incident upon the emission probe disposed in front of the front end of the optical fiber.
The present inventor has developed various contact type probes and they have been widely used. In order to incise the tissue by using such a contact type probe, it is necessary to cause the probe to track an incision line on the surface of the tissue on one side thereof a plurality of times. When a fine blood vessel is cut, bleeding is less since the blood vessel where it is irradiated with the laser light will be solidified. However, when a blood vessel having a diameter of 1.5 mm or more is to be cut, it is usually necessary to preliminarily knot the blood vessel on both sides of the cut position with a suture to prevent bleeding.
As far as one light guide probe is used in such a manner, it is necessary to knot a large blood vessel on the both sides of the cutting position every time when the blood vessel is cut. This will hinder the ready and easy operation. Although a suture which is biocompatible to the living tissue in recovery after operation has been developed, it is necessary to remove the suture from the tissue after opening the body again if the concrescence between the suture and the living tissue is not complete. This removing operation is hard on the patient.
If an organ which is easy to bleed such as liver is to be cut it is necessary to gradually cut the organ along the same incision line many times in order to minimize bleeding. It takes a long time to conduct the operation, and attention should be paid.
In case in which one of an organ has been already incised and the other has not been incised yet, even if irradiation with laser light is conducted plural times when some organ is to be cut or incised, the tissue behind the tissue to be treated is inevitably slightly irradiated with laser light by accident. On the other hand, in case of the projecting tumor, it has been known that the tumor is cut from the neck thereof with an annular radio frequency snare which is disposed around the tumor. This operation is not excellent in hemostasis. If physiological saline is used, an electric shock is given to the tissue and burn may occur in the vicinity of the diseased portion so that the tissue is unwatedly damaged.
From this point of view, in order to conduct at proper and quick surgical operation, cutting and incision of the tissue should be conducted one time operation, the hemostasis should be high and only target tissue should be able to be cut or incised and incision is possible without knotting if the target tissue is a blood vessel.
Therefore, the present inventor has proposed an apparatus for treatment which has overcome these problems in Japanese Unexamined patent publication No. Hei 3-218742. The apparatus for treatment using the laser light irradiation has two light guide probes which faces each other. The laser light emitting portions of the two light guide probes can be in and out of contact with each other by the surgical operators actuation. The laser light is incident to respective light guide probes via respective laser light transmitting systems. A target tissue to be treated is disposed between the laser light emitting portions of the light guide probes.
However, since the two light guide probes are linked to each other at their base ends so that they are substantially V-shaped and the target tissue is to be tweezed with a tweezers in prior art, the width of the apparatus per se and the range of actuation of the apparatus can not be made small. The prior art apparatus is suitable for the treatment in an open position in laparotomy, but is not suitable for the application in which the apparatus is inserted into a body cavity together with an endoscope.
In the above-mentioned prior art, it is necessary to pay attention so that the light guide probe will not be contact with the tissue in the vicinity of a target position to be treated even after the incision is completed since the light guide probe per se generates heat on incision.
Although the laser light is mainly directed toward the target position to be treated, some of the laser light is slightly incident upon the tissue other than the tissue to be treated. Accordingly, there is the risk in which the tissue in the vicinity of the target position to be treated will be damaged.
Although the prior art is capable of conducting incision and bleeding stopping simultaneously, the prior art is not ideal since the temperatures optimal for the incision and solidification of the living tissue are different.